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[PMID]:28956599
[Au] Autor:Reddick JJ; Sirkisoon S; Dahal RA; Hardesty G; Hage NE; Booth WT; Quattlebaum AL; Mills SN; Meadows VG; Adams SLH; Doyle JS; Kiel BE
[Ad] Endereço:Department of Chemistry and Biochemistry, University of North Carolina at Greensboro , Greensboro, North Carolina 27402, United States.
[Ti] Título:First Biochemical Characterization of a Methylcitric Acid Cycle from Bacillus subtilis Strain 168.
[So] Source:Biochemistry;56(42):5698-5711, 2017 Oct 24.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The genome of Bacillus subtilis strain 168 contains the mother cell metabolic gene (mmg) operon that encodes homologues from the methylcitric acid cycle. We showed that the three genes, mmgDE and yqiQ(mmgF), provide three of the five steps of the methylcitric acid cycle. We also showed that the fourth step can be supplied by citB (aconitase), and we suggest that the fifth missing step, the propionyl-CoA synthetase, is probably skipped because the ß-oxidation of methyl-branched fatty acids by the enzymes encoded by mmgABC should produce propionyl-CoA. We also noted interesting enzymology for MmgD and MmgE. First, MmgD is a bifunctional citrate synthase/2-methylcitrate synthase with 2.3-fold higher activity as a 2-methylcitrate synthase. This enzyme catalyzes the formation of either (2S,3R)- or (2R,3S)-2-methylcitrate, but reports of 2-methylcitrate synthases from other species indicated that they produced the (2S,3S) isomer. However, we showed that MmgD and PrpC (from Escherichia coli) in fact produce the same stereoisomer. Second, the MmgE enzyme is not a stereospecific 2-methylcitrate dehydratase because it can dehydrate at least two of the four diastereomers of 2-methylcitrate to yield either (E)-2-methylaconitate or (Z)-2-methylaconitate. We also showed for the first time that the E. coli homologue PrpD exhibited the same lack of stereospecificity. However, the physiological pathways proceed via (Z)-2-methylaconitate, which served as the substrate for the citB enzyme in the synthesis of 2-methylisocitrate. We completed our characterization of this pathway by showing that the 2-methylisocitrate produced by CitB is converted to pyruvate and succinate by the enzyme YqiQ(MmgF).
[Mh] Termos MeSH primário: Bacillus subtilis/metabolismo
Citratos/metabolismo
Óperon/fisiologia
Oxo-Ácido-Liases/metabolismo
[Mh] Termos MeSH secundário: Bacillus subtilis/genética
Escherichia coli/genética
Escherichia coli/metabolismo
Proteínas de Escherichia coli/genética
Proteínas de Escherichia coli/metabolismo
Hidroliases/genética
Hidroliases/metabolismo
Oxirredução
Oxo-Ácido-Liases/genética
Estereoisomerismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Citrates); 0 (Escherichia coli Proteins); 6061-96-7 (2-methylcitric acid); EC 2.3.3.5 (2-methylcitrate synthase); EC 4.1.3.- (Oxo-Acid-Lyases); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.79 (methylcitrate dehydratase, E coli)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171027
[Lr] Data última revisão:
171027
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170929
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00778


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[PMID]:28848047
[Au] Autor:Yao P; Sun H; Xu C; Chen T; Zou B; Jiang P; Du W
[Ad] Endereço:From the School of Life Sciences, Tsinghua University, Beijing 100084, China and.
[Ti] Título:Evidence for a direct cross-talk between malic enzyme and the pentose phosphate pathway via structural interactions.
[So] Source:J Biol Chem;292(41):17113-17120, 2017 Oct 13.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Recent studies have revealed that the oxidative entose hosphate athway (PPP), malic enzyme (ME), and folate metabolism are the three major routes for generating cellular NADPH, a key cofactor involved in redox control and reductive biosynthesis. Many tumor cells exhibit altered NADPH metabolism to fuel their rapid proliferation. However, little is known about how NADPH metabolism is coordinated in tumor cells. Here we report that ME1 increases the PPP flux by forming physiological complexes with 6-phosphogluconate dehydrogenase (6PGD). We found that ME1 and 6PGD form a hetero-oligomer that increases the capability of 6PGD to bind its substrate 6-phosphogluconate. Through activating 6PGD, ME1 enhances NADPH generation, PPP flux, and tumor cell growth. Interestingly, although ME1 could bind either the dimer-defect mutant 6PGD (K294R) or the NADP -binding defect 6PGD mutants, only 6PGD (K294R) activity was induced by ME1. Thus, ME1/6PGD hetero-complexes may mimic the active oligomer form of 6PGD. Together, these findings uncover a direct cross-talk mechanism between ME1 and PPP, may reveal an alternative model for signaling transduction via protein conformational simulation, and pave the way for better understanding how metabolic pathways are coordinated in cancer.
[Mh] Termos MeSH primário: Malato Desidrogenase/metabolismo
Proteínas de Neoplasias/metabolismo
Neoplasias/enzimologia
Via de Pentose Fosfato
Multimerização Proteica
Transdução de Sinais
[Mh] Termos MeSH secundário: Linhagem Celular Tumoral
Gluconatos/química
Gluconatos/metabolismo
Seres Humanos
Hidroliases/química
Hidroliases/genética
Hidroliases/metabolismo
Malato Desidrogenase/química
Malato Desidrogenase/genética
Mutação de Sentido Incorreto
NADP/química
NADP/genética
NADP/metabolismo
Proteínas de Neoplasias/química
Proteínas de Neoplasias/genética
Neoplasias/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Gluconates); 0 (Neoplasm Proteins); 53-59-8 (NADP); EC 1.1.1.37 (Malate Dehydrogenase); EC 1.1.1.39 (malate dehydrogenase (decarboxylating)); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.12 (phosphogluconate dehydratase); W31WK7B8U0 (6-phosphogluconic acid)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171019
[Lr] Data última revisão:
171019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170830
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.810309


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[PMID]:28791799
[Au] Autor:Peón A; Robles A; Blanco B; Convertino M; Thompson P; Hawkins AR; Caflisch A; González-Bello C
[Ad] Endereço:Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares, CIQUS, and Departamento de Química Orgánica, Universidade de Santiago de Compostela, calle Jenaro de la Fuente s/n, 15782, Santiago de Compostela, Spain.
[Ti] Título:Reducing the Flexibility of Type II Dehydroquinase for Inhibition: A Fragment-Based Approach and Molecular Dynamics Study.
[So] Source:ChemMedChem;12(18):1512-1524, 2017 Sep 21.
[Is] ISSN:1860-7187
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:A multidisciplinary approach was used to identify and optimize a quinazolinedione-based ligand that would decrease the flexibility of the substrate-covering loop (catalytic loop) of the type II dehydroquinase from Helicobacter pylori. This enzyme, which is essential for the survival of this bacterium, is involved in the biosynthesis of aromatic amino acids. A computer-aided fragment-based protocol (ALTA) was first used to identify the aromatic fragments able to block the interface pocket that separates two neighboring enzyme subunits and is located at the active site entrance. Chemical modification of its non-aromatic moiety through an olefin cross-metathesis and Seebach's self-reproduction of chirality synthetic principle allowed the development of a quinazolinedione derivative that disables the catalytic loop plasticity, which is essential for the enzyme's catalytic cycle. Molecular dynamics simulations revealed that the ligand would force the catalytic loop into an inappropriate arrangement for catalysis by strong interactions with the catalytic tyrosine and by expelling the essential arginine out of the active site.
[Mh] Termos MeSH primário: Desenho de Drogas
Inibidores Enzimáticos/metabolismo
Hidroliases/metabolismo
Simulação de Dinâmica Molecular
[Mh] Termos MeSH secundário: Antibacterianos/síntese química
Antibacterianos/química
Antibacterianos/metabolismo
Sítios de Ligação
Domínio Catalítico
Inibidores Enzimáticos/química
Helicobacter pylori/enzimologia
Hidroliases/antagonistas & inibidores
Ligantes
Quinazolinonas/química
Quinazolinonas/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Enzyme Inhibitors); 0 (Ligands); 0 (Quinazolinones); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.10 (3-dehydroquinate dehydratase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171009
[Lr] Data última revisão:
171009
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170810
[St] Status:MEDLINE
[do] DOI:10.1002/cmdc.201700396


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[PMID]:28789944
[Au] Autor:Lone MY; Athar M; Gupta VK; Jha PC
[Ad] Endereço:School of Chemical Sciences, Central University of Gujarat, Gandhinagar 382030, Gujarat, India.
[Ti] Título:Prioritization of natural compounds against mycobacterium tuberculosis 3-dehydroquinate dehydratase: A combined in-silico and in-vitro study.
[So] Source:Biochem Biophys Res Commun;491(4):1105-1111, 2017 Sep 30.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Enormous efforts have been endeavored to develop inhibitors against the potential therapeutic target, mycobacterium tuberculosis 3-dehydroquinate dehydratase (MtbDHQase) to combat resistance. Over a dozen of small molecules have been crystallized to characterize the structural basis of the inhibition. However, the studies accomplished so far, have not incorporated all the essential interactions of these complexes simultaneously, to identify the novel inhibitors. Therefore, an attempt was made to construct the pharmacophore models and identify the essential features that can be employed to prioritize the molecules against this target. Based on validation and expertise, we have identified such complimentary features from the natural compounds that can be used as initial hits. Subsequently, these hits were tested for their inhibitory roles in reducing the mycobacterium tuberculosis (Mtb) culture growth. Moreover, the docking simulations were performed to seek the possible interactions accountable for the activity of these candidates against MtbDHQase.
[Mh] Termos MeSH primário: Antituberculosos/farmacologia
Produtos Biológicos/farmacologia
Inibidores Enzimáticos/farmacologia
Hidroliases/antagonistas & inibidores
Simulação de Dinâmica Molecular
Mycobacterium tuberculosis/efeitos dos fármacos
[Mh] Termos MeSH secundário: Antituberculosos/química
Produtos Biológicos/química
Inibidores Enzimáticos/química
Hidroliases/metabolismo
Testes de Sensibilidade Microbiana
Conformação Molecular
Mycobacterium tuberculosis/enzimologia
Mycobacterium tuberculosis/crescimento & desenvolvimento
Relação Estrutura-Atividade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Antitubercular Agents); 0 (Biological Products); 0 (Enzyme Inhibitors); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.10 (3-dehydroquinate dehydratase)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170810
[St] Status:MEDLINE


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[PMID]:28784662
[Au] Autor:Sawai M; Uchida Y; Ohno Y; Miyamoto M; Nishioka C; Itohara S; Sassa T; Kihara A
[Ad] Endereço:From the Faculty of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812 and.
[Ti] Título:The 3-hydroxyacyl-CoA dehydratases HACD1 and HACD2 exhibit functional redundancy and are active in a wide range of fatty acid elongation pathways.
[So] Source:J Biol Chem;292(37):15538-15551, 2017 Sep 15.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Differences among fatty acids (FAs) in chain length and number of double bonds create lipid diversity. FA elongation proceeds via a four-step reaction cycle, in which the 3-hydroxyacyl-CoA dehydratases (HACDs) HACD1-4 catalyze the third step. However, the contribution of each HACD to 3-hydroxyacyl-CoA dehydratase activity in certain tissues or in different FA elongation pathways remains unclear. is specifically expressed in muscles and is a myopathy-causative gene. Here, we generated KO mice and observed that these mice had reduced body and skeletal muscle weights. In skeletal muscle, mRNA expression was by far the highest among the However, we observed only an ∼40% reduction in HACD activity and no changes in membrane lipid composition in -KO skeletal muscle, suggesting that some HACD activities are redundant. Moreover, when expressed in yeast, both HACD1 and HACD2 participated in saturated and monounsaturated FA elongation pathways. Disruption of in the haploid human cell line HAP1 significantly reduced FA elongation activities toward both saturated and unsaturated FAs, and double disruption resulted in a further reduction. Overexpressed HACD3 exhibited weak activity in saturated and monounsaturated FA elongation pathways, and no activity was detected for HACD4. We therefore conclude that HACD1 and HACD2 exhibit redundant activities in a wide range of FA elongation pathways, including those for saturated to polyunsaturated FAs, with HACD2 being the major 3-hydroxyacyl-CoA dehydratase. Our findings are important for furthering the understanding of the molecular mechanisms in FA elongation and diversity.
[Mh] Termos MeSH primário: Ácidos Graxos/metabolismo
Hidroliases/metabolismo
Proteínas de Membrana/metabolismo
Músculo Esquelético/enzimologia
Mioblastos Esqueléticos/enzimologia
Proteínas Tirosina Fosfatases/metabolismo
[Mh] Termos MeSH secundário: Animais
Sistemas CRISPR-Cas
Domínio Catalítico
Linhagem Celular Tumoral
Células Cultivadas
Ácidos Graxos/química
Regulação Enzimológica da Expressão Gênica
Seres Humanos
Hidroliases/genética
Isoenzimas/genética
Isoenzimas/metabolismo
Masculino
Proteínas de Membrana/genética
Camundongos Knockout
Estrutura Molecular
Peso Molecular
Músculo Esquelético/citologia
Músculo Esquelético/patologia
Doenças Musculares/enzimologia
Doenças Musculares/genética
Doenças Musculares/patologia
Mioblastos Esqueléticos/citologia
Mioblastos Esqueléticos/patologia
Proteínas Tirosina Fosfatases/genética
Proteínas Recombinantes de Fusão/metabolismo
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fatty Acids); 0 (Isoenzymes); 0 (Membrane Proteins); 0 (Recombinant Fusion Proteins); EC 3.1.3.48 (PTPLA protein, human); EC 3.1.3.48 (Protein Tyrosine Phosphatases); EC 3.1.3.48 (Ptpla protein, mouse); EC 4.2.1.- (D-3-hydroxyacyl CoA dehydratase); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.- (PTPLB protein, human)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170927
[Lr] Data última revisão:
170927
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170809
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M117.803171


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[PMID]:28726102
[Au] Autor:Maksimova YG; Gorbunova AN; Demakov VA
[Ad] Endereço:Institute of Ecology and Genetics of Microorganisms, Ural Branch, Russian Academy of Sciences, Perm, 614081, Russia. maks@iegm.ru.
[Ti] Título:Stereoselective biotransformation of phenylglycine nitrile by heterogeneous biocatalyst based on immobilized bacterial cells and enzyme preparation.
[So] Source:Dokl Biochem Biophys;474(1):183-185, 2017 May.
[Is] ISSN:1608-3091
[Cp] País de publicação:Russia (Federation)
[La] Idioma:eng
[Ab] Resumo:We studied the effect of a heterogeneous environment on the stereoselectivity of transformation of racemic phenylglycine nitrile. Immobilized biocatalysts were prepared by adhesion of Pseudomonas fluorescens C2 cells on carbon-containing supports and covalent crosslinking of nitrile hydratase and amidase of Rhodococcus rhodochrous 4-1 to activated chitosan as well as by the method of cross-linked aggregates. At a reaction duration of 20 h, the ratio of phenylglycine stereoisomers changes depending on the presence of support in medium. The highest optical purity of the product (enantiomeric excess of L-phenylglycine solution, 98%) is achieved when enzyme aggregates of nitrile hydratase and amidase cross-linked with 0.1% glutaraldehyde are used as a biocatalyst.
[Mh] Termos MeSH primário: Acetonitrilos/química
Acetonitrilos/metabolismo
Amidoidrolases/metabolismo
Biocatálise
Hidroliases/metabolismo
Pseudomonas/citologia
[Mh] Termos MeSH secundário: Amidoidrolases/química
Aderência Bacteriana
Biotransformação
Células Imobilizadas/citologia
Hidroliases/química
Hidrólise
Rhodococcus/enzimologia
Estereoisomerismo
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Acetonitriles); 0 (phenylglycine nitrile); EC 3.5.- (Amidohydrolases); EC 3.5.1.4 (amidase); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.- (nitrile hydratase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170906
[Lr] Data última revisão:
170906
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170721
[St] Status:MEDLINE
[do] DOI:10.1134/S1607672917030139


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[PMID]:28644864
[Au] Autor:Lan Y; Zhang X; Liu Z; Zhou L; Shen R; Zhong X; Cui W; Zhou Z
[Ad] Endereço:Key Laboratory of Industrial Biotechnology (Ministry of Education), School of Biotechnology, Jiangnan University, Wuxi, China.
[Ti] Título:Overexpression and characterization of two types of nitrile hydratases from Rhodococcus rhodochrous J1.
[So] Source:PLoS One;12(6):e0179833, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Nitrile hydratase (NHase) from Rhodococcus rhodochrous J1 is widely used for industrial production of acrylamide and nicotinamide. However, the two types of NHases (L-NHase and H-NHase) from R. rhodochrous J1 were only slightly expressed in E. coli by routine methods, which limits the comprehensive and systematic characterization of the enzyme properties. We successfully expressed the two types of recombinant NHases in E. coli by codon-optimization, engineering of Ribosome Binding Site (RBS) and spacer sequences. The specific activity of the purified L-NHase and H-NHase were 400 U/mg and 234 U/mg, respectively. The molecular mass of L-NHase and H-NHase was identified to be 94 kDa and 504 kDa, respectively, indicating that the quaternary structure of the two types of NHases was the same as those in R. rhodochrous J1. H-NHase exhibited higher substrate and product tolerance than L-NHase. Moreover, higher activity and shorter culture time were achieved in recombinant E. coli, and the whole cell catalyst of recombinant E. coli harboring H-NHase has equivalent efficiency in tolerance to the high-concentration product relative to that in R. rhodochrous J1. These results indicate that biotransformation of nitrile by R. rhodochrous J1 represents a potential alternative to NHase-producing E. coli.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Hidroliases/genética
Hidroliases/metabolismo
Rhodococcus/enzimologia
Rhodococcus/genética
[Mh] Termos MeSH secundário: Proteínas de Bactérias/síntese química
Proteínas de Bactérias/isolamento & purificação
Sítios de Ligação/genética
Biotransformação
Códon
Eletroforese em Gel de Poliacrilamida
Estabilidade Enzimática
Escherichia coli/enzimologia
Expressão Gênica
Engenharia Genética
Hidroliases/síntese química
Hidroliases/isolamento & purificação
RNA Mensageiro/metabolismo
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/metabolismo
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Codon); 0 (RNA, Messenger); 0 (Recombinant Proteins); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.- (nitrile hydratase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170918
[Lr] Data última revisão:
170918
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170624
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0179833


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[PMID]:28559297
[Au] Autor:Watanabe S; Fukumori F; Miyazaki M; Tagami S; Watanabe Y
[Ad] Endereço:Department of Bioscience, Graduate School of Agriculture, Ehime University, Matsuyama, Ehime, Japan irab@agr.ehime-u.ac.jp.
[Ti] Título:Characterization of a Novel -3-Hydroxy-l-Proline Dehydratase and a -3-Hydroxy-l-Proline Dehydratase from Bacteria.
[So] Source:J Bacteriol;199(16), 2017 Aug 15.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Hydroxyprolines, such as -4-hydroxy-l-proline (T4LHyp), -3-hydroxy-l-proline (T3LHyp), and -3-hydroxy-l-proline (C3LHyp), are present in some proteins including collagen, plant cell wall, and several peptide antibiotics. In bacteria, genes involved in the degradation of hydroxyproline are often clustered on the genome (l-Hyp gene cluster). We recently reported that an aconitase X (AcnX)-like gene from an l-Hyp gene cluster functions as a monomeric C3LHyp dehydratase (AcnX ). However, the physiological role of C3LHyp dehydratase remained unclear. We here demonstrate that NBRC 102289, an aerobic nitrogen-fixing bacterium, robustly grows using not only T4LHyp and T3LHyp but also C3LHyp as the sole carbon source. The small and large subunits of the gene ( and , respectively) from NBRC 102289 are located separately from the l-Hyp gene cluster and encode a C3LHyp dehydratase with a novel heterodimeric structure (AcnX ). A strain disrupted in the gene did not grow on C3LHyp, suggesting its involvement in C3LHyp metabolism. Furthermore, C3LHyp induced transcription of not only the genes but also the gene encoding Δ -pyrroline-2-carboxylate reductase, which is involved in T3LHyp, d-proline, and d-lysine metabolism. On the other hand, the l-Hyp gene cluster of some other bacteria contained not only the AcnX gene but also two putative proline racemase-like genes ( and ). Despite having the same active sites (a pair of Cys/Cys) as hydroxyproline 2-epimerase, which is involved in the metabolism of T4LHyp, the dominant reaction by HypA2 was clearly the dehydration of T3LHyp, a novel type of T3LHyp dehydratase that differed from the known enzyme (Cys/Thr). More than 50 years after the discovery of -4-hydroxy-l-proline (generally called l-hydroxyproline) degradation in aerobic bacteria, its genetic and molecular information has only recently been elucidated. l-Hydroxyproline metabolic genes are often clustered on bacterial genomes. These loci frequently contain a hypothetical gene(s), whose novel enzyme functions are related to the metabolism of -3-hydroxyl-proline and/or -3-hydroxyl-proline, a relatively rare l-hydroxyproline in nature. Several l-hydroxyproline metabolic enzymes show no sequential similarities, suggesting their emergence by convergent evolution. Furthermore, transcriptional regulation by -4-hydroxy-l-proline, -3-hydroxy-l-proline, and/or -3-hydroxy-l-proline significantly differs between bacteria. The results of the present study show that several l-hydroxyprolines are available for bacteria as carbon and energy sources and may contribute to the discovery of potential metabolic pathways of another hydroxyproline(s).
[Mh] Termos MeSH primário: Azospirillum brasilense/enzimologia
Hidroliases/isolamento & purificação
Hidroliases/metabolismo
Hidroxiprolina/metabolismo
[Mh] Termos MeSH secundário: Azospirillum brasilense/genética
Azospirillum brasilense/crescimento & desenvolvimento
Azospirillum brasilense/metabolismo
Carbono/metabolismo
Técnicas de Inativação de Genes
Hidroxiprolina/genética
Família Multigênica
Subunidades Proteicas/genética
Subunidades Proteicas/metabolismo
Transcrição Genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Protein Subunits); 7440-44-0 (Carbon); EC 4.2.1.- (Hydro-Lyases); RMB44WO89X (Hydroxyproline)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170809
[Lr] Data última revisão:
170809
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170601
[St] Status:MEDLINE


  9 / 4951 MEDLINE  
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[PMID]:28528741
[Au] Autor:Xu H; Hao S; Gan F; Wang H; Xu J; Liu D; Huang K
[Ad] Endereço:College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China; Institute of Nutritional and Metabolic Disorders in Domestic Animals and Fowls, Nanjing Agricultural University, Nanjing 210095, Jiangsu Province, China.
[Ti] Título:In vitro immune toxicity of ochratoxin A in porcine alveolar macrophages: A role for the ROS-relative TLR4/MyD88 signaling pathway.
[So] Source:Chem Biol Interact;272:107-116, 2017 Jun 25.
[Is] ISSN:1872-7786
[Cp] País de publicação:Ireland
[La] Idioma:eng
[Ab] Resumo:Ochratoxin A (OTA) frequently contaminates a wide variety of food and feeds, inducing immune toxicity of animals. However, the underlying mechanism remains unclear. In the present study, porcine alveolar macrophages (PAMs) cell line 3D4/21 were chosen as a model, and treated by various concentrations of OTA. The results showed that OTA induced immune toxicity of PAMs in a dose-dependent manner, as demonstrated by cell viability, LDH release, Annexin V/PI staining, Bcl-2/Bax mRNA ratio, and pro-inflammatory cytokines expression. OTA increased intracellular ROS levels of PAMs by flow cytometry and confocal microscopy. NAC, a commonly used antioxidant, alleviated the OTA-induced increase of ROS production, apoptosis, and LDH release and decrease of cell viability. Furthermore, OTA enhanced the mRNA and protein expression of TLR4 and MyD88 and the phosphorylation of ERK1/2, p38, and NF-κB p65. Knockdown of TLR4 by using a TLR4-specific siRNA alleviated the OTA-induced immune toxicity. These data indicate that OTA induced immune toxicity via ROS-relative TLR4/MyD88 signaling pathway in PAMs.
[Mh] Termos MeSH primário: Ocratoxinas/toxicidade
Espécies Reativas de Oxigênio/metabolismo
Transdução de Sinais/efeitos dos fármacos
Receptor 4 Toll-Like/metabolismo
[Mh] Termos MeSH secundário: Animais
Linhagem Celular
Sobrevivência Celular/efeitos dos fármacos
Expressão Gênica/efeitos dos fármacos
Hidroliases/metabolismo
Interleucina-1beta/genética
Interleucina-1beta/metabolismo
Macrófagos Alveolares/citologia
Macrófagos Alveolares/efeitos dos fármacos
Macrófagos Alveolares/metabolismo
Proteína Quinase 3 Ativada por Mitógeno/metabolismo
Fator 88 de Diferenciação Mieloide/metabolismo
Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
RNA Interferente Pequeno/metabolismo
Suínos
Receptor 4 Toll-Like/antagonistas & inibidores
Receptor 4 Toll-Like/genética
Fator de Transcrição RelA/metabolismo
Fator de Necrose Tumoral alfa/genética
Fator de Necrose Tumoral alfa/metabolismo
Proteína X Associada a bcl-2/metabolismo
Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Interleukin-1beta); 0 (Myeloid Differentiation Factor 88); 0 (Ochratoxins); 0 (Proto-Oncogene Proteins c-bcl-2); 0 (RNA, Small Interfering); 0 (Reactive Oxygen Species); 0 (Toll-Like Receptor 4); 0 (Transcription Factor RelA); 0 (Tumor Necrosis Factor-alpha); 0 (bcl-2-Associated X Protein); 1779SX6LUY (ochratoxin A); EC 2.7.11.24 (Mitogen-Activated Protein Kinase 3); EC 2.7.11.24 (p38 Mitogen-Activated Protein Kinases); EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.54 (lactate dehydratase)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170620
[Lr] Data última revisão:
170620
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170523
[St] Status:MEDLINE


  10 / 4951 MEDLINE  
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[PMID]:28520398
[Au] Autor:Stein N; Gumataotao N; Hajnas N; Wu R; Lankathilaka KPW; Bornscheuer UT; Liu D; Fiedler AT; Holz RC; Bennett B
[Ad] Endereço:Department of Physics, Marquette University , 540 North 15th Street, Milwaukee, Wisconsin 53233, United States.
[Ti] Título:Multiple States of Nitrile Hydratase from Rhodococcus equi TG328-2: Structural and Mechanistic Insights from Electron Paramagnetic Resonance and Density Functional Theory Studies.
[So] Source:Biochemistry;56(24):3068-3077, 2017 Jun 20.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Iron-type nitrile hydratases (NHases) contain an Fe(III) ion coordinated in a characteristic "claw setting" by an axial cysteine thiolate, two equatorial peptide nitrogens, the sulfur atoms of equatorial cysteine-sulfenic and cysteine-sulfinic acids, and an axial water/hydroxyl moiety. The cysteine-sulfenic acid is susceptible to oxidation, and the enzyme is traditionally prepared using butyric acid as an oxidative protectant. The as-prepared enzyme exhibits a complex electron paramagnetic resonance (EPR) spectrum due to multiple low-spin (S = / ) Fe(III) species. Four distinct signals can be assigned to the resting active state, the active state bound to butyric acid, an oxidized Fe(III)-bis(sulfinic acid) form, and an oxidized complex with butyric acid. A combination of comparison with earlier work, development of methods to elicit individual signals, and design and application of a novel density functional theory method for reproducing g tensors to unprecedentedly high precision was used to assign the signals. These species account for the previously reported EPR spectra from Fe-NHases, including spectra observed upon addition of substrates. Completely new EPR signals were observed upon addition of inhibitory boronic acids, and the distinctive g features of these signals were replicated in the steady state with the slow substrate acetonitrile. This latter signal constitutes the first EPR signal from a catalytic intermediate of NHase and is assigned to a key intermediate in the proposed catalytic cycle. Earlier, apparently contradictory, electron nuclear double resonance reports are reconsidered in the context of this work.
[Mh] Termos MeSH primário: Hidroliases/química
Ressonância Magnética Nuclear Biomolecular
Teoria Quântica
Rhodococcus equi/enzimologia
[Mh] Termos MeSH secundário: Hidroliases/metabolismo
Conformação Proteica
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 4.2.1.- (Hydro-Lyases); EC 4.2.1.- (nitrile hydratase)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171004
[Lr] Data última revisão:
171004
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170519
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.6b00876



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